Add utilities to create IPv6 ICMP messages.

The utilities replace the ones from IpClientIntegrationTests. Original
Kotlin implementation is aosp/1440812.

Bug: 168868607
Test: atest NetworkStackIntegrationTest
Change-Id: I1c050ae42d99f541eeaa3dcd80a53574ab9bc1c3
12 files changed
tree: b90cddbc9c81ab57538640bb8d82b1706a4f7532
  1. staticlibs/